1. Field of the Invention
The present invention relates to suppression of angiogenesis.
2. Description of the Related Art
Angiogenesis is a physiological phenomenon in the human body of healthy adults, and “a process of forming new blood vessels from existing vessels in the body.” Therefore, angiogenesis is a physiological phenomenon necessary, for the body.
However, the angiogenesis for supply of nutrients to tumor in tumor growth and metastasis or to hypertrophied tissues in tissue hypertrophy is confirmed, in tumor diseases, various ophthalmic diseases, chronic inflammation, or other diseases such as cancer, age-related macular degeneration, diabetic retinopathy, psoriasis, rheumatoid arthritis and osteoarthritis.
For these reasons, it is considered that these diseases can be prevented or treated by restoring the balance to a moderate state in healthy subjects between “angiogenesis” and “suppression of angiogenesis”.
In recent years, an inhibitor of vascular endothelial growth factor (VEGF) which is known as the promoting factor of angiogenesis, that is, a kind of angiogenesis inhibitor has been clinically applied. Examples of the VEGF inhibitor may include an anti-VEGF antibody and an anti-VEGF aptamer. By using these compounds, it was confirmed that the effectiveness of the angiogenesis inhibitor as a therapeutic agent for some kinds of cancer diseases, diabetic retinopathy, or age-related macular degeneration. However, it has been reported that the existing VEGF inhibitors have disadvantages such as side effects including hemorrhage, hypertension, and cardiotoxicity, low reproducibility of their effect, and variation of their effect depending on the species. For these disadvantages, it is sometimes difficult to administer the existing angiogenesis inhibitors to a patient.
Antioxidants such as vitamin C, vitamin E, and flavonoid are also known as compounds having an angiogenesis inhibitory effect. However, since the molecular weight of the compounds is high, these compounds have problems such as low absorption and low intercellular penetration. Therefore, these compounds seem to be less suitable for practical use.